Scientists work to stop deadly mite

A tiny pest brought the U.S. honey bee industry to its knees, but a Louisiana scientist found a remedy in remote Russia.

Two different types of mites were detected in American honey bees in the mid-1980s. “Tracheal mites showed up in 1984. Then shortly after that we had varroa mites,” said professional beekeeper Charlie Harper of Carencro. “Before then, beekeeping was a lot easier.”

For a few years, pesticides could control varroa populations — the biggest threat to honey bees — but eventually the mites became immune to chemicals, Harper said, using graphic but effective terms to describe how varroa mites harm bees. “A varroa mite on you would be like a tick the size of a rat sucking your blood.”

In addition, he said, varroa mites transmit diseases to bees.

Varroa mites are capable of 10 to 15 generations in a year, according to Tom Rinderer, director of the U.S. Department of Agriculture's Bee Lab in Baton Rouge, La., and an adjunct LSU AgCenter entomology professor.

“People were losing 80 percent of their colonies during the winter,” Rinderer said.

LSU AgCenter entomologist Dale Pollet said honey bees have a significant role in agriculture, providing $400 million in pollination in Louisiana, $4 million in honey production and $300,000 in sales of apiary supplies.

“About 60 percent of the food we eat is directly or indirectly due to bees,” Pollet said of the bees' roles in pollination and honey production.

The demand for a solution prompted Rinderer to find an area where honey bees had adapted to mites. He knew of a Siberian area of Primorsky in Russia where Ukranian emigrants brought bees with them when they migrated there in the mid-1800s.

Originally the bees weren't exposed to varroa mites until being moved to their Siberian home, Rinderer said. The bees that could survive the harsh winters and endure varroa mites were the only ones to prosper, he said, and beekeepers probably used no breeding techniques.

“I think there was an opportunity for natural selection to take place,” he said.

After the USSR was formed, the Primorsky naval port of Vladivostok was closed to outsiders because of its military activities there, Rinderer said, but military officers assigned to the seaport enjoyed beekeeping as a hobby.

After the USSR collapsed, Rinderer ventured to Primorsky to explore the possibility of bringing Russian honey bees to the United States as a possible solution to the varroa problem.

The Primorsky beekeepers didn't seem to be worried about the mite problem, Rinderer said. “They were much more casual about it,” he said.

But getting the honey bees from Russia to Rinderer's lab in Baton Rouge wasn't a casual endeavor. “It took two years just to get bees in Vladivostok to a bee yard here,” he said.

After that, experimental colonies were established at an isolated location in Louisiana near Grand Isle.

Breeding was aimed at taking only the best colonies before releasing a line of queens.

The breeding program is even more intensive now, Rinderer said, with selections made to obtain the best queens. Russian queens are being produced in Iowa to subject them to harsh winters, and in Mississippi and Louisiana, with the best chosen for breeding lines.

Beekeepers are making the transition from Italian bees to Russians, but the change takes some adjustment. “They're a different bee,” Rinderer said. “They look pathetic in the springtime.”

After winter, the colony is small — with no brood being produced until late spring, he explained. “They look like they're on the verge of death.”

The Russians aren't fooled by the sudden warm-ups of Louisiana's early spring, he said, but once the pollen flow begins, the Russian bees shift into high gear. “They sit back until it's obvious spring is here,” Rinderer said.

In fact, beekeepers have to prepare extra hive space for expansion, he said.

Russian bees suffer only a third to half of the mites that plague Italian hives, Rinderer said, and the new lines have enabled some beekeepers in New York to forego using chemicals to control mites. “I have some confidence in the next few years we will be producing bees that don't need chemicals at all,” he said.

Harper said his beekeeping operation depends less on chemical defenses. “I'm going without chemical treatment on the Russian hives I have,” said Harper, vice president of the Louisiana Beekeepers Association.

Harper sells Russian breeder queens to other queen bee breeders. This year he shipped queens to New York, California, Florida, Mississippi, Texas, Arkansas, both Carolinas and Georgia. After Canada opened its border for U.S. queen shipments, he sent an order there for six queens.

To make a queen, a larva is placed in a plastic cell, positioned vertically in the hive, unlike the other cells in a hive that are horizontal, and worker bees feed the larva royal jelly.

The queen mates with drones, then starts laying up to 2,000 eggs per day. “That's all a queen is — an egg-laying machine,” Harper said.

His customers will use the $500 breeder queens to produce new queens that will be sold for $10 to $15 each to beekeepers.

The Russians are immune to tracheal mites that block bees' airways, and they have resistance to parasitic varroa mites.

Russian hives also aren't as conducive for mites to reproduce.

Pollination from honey bees is essential for many agricultural crops that aren't self-pollinating. Harper said the almond industry in California relies heavily on honey bees, and almond farmers had to cope with a bee shortage this year. Crops such as pears, cherries, apples, melons and cucumbers also require pollination.

In southern Louisiana, honey bees get most of their honey from tallow trees, also known in some areas as chicken trees, he said. “A lot of people don't realize tallow trees are good for something,” Harper said.

All honey bees in the New World were imported, Rinderer said, with Italian bees becoming the preferred breed.

The Bee Act of 1911 prohibited importation of honey bees into the United States, but someone apparently violated that law, inadvertently introducing the varroa mites into American hives, Rinderer said.

A study conducted by the USDA Bee Lab indicates Louisiana may be spared from the spread of Africanized bees, commonly known by the exaggerated name of “killer bees.” The study indicates that in more than a decade the bees have not been able to migrate to areas with more than 55 inches of annual rainfall.

“Africanized bees seemed to have reached their limit of spreading,” Rinderer said. “They seem to be stuck in east Texas, and the ones that are stuck there are hybridized and not anything like pure African.”